I see the following sequence:
1. Defective mitochondria ignite the SASP:
https://www.nature.c...1580-020-0228-x
2. SASP induces macrophage proliferation and CD38 expression
Declining tissue nicotinamide adenine dinucleotide (NAD) levels are linked to ageing and its associated diseases. However, the mechanism for this decline is unclear. Here, we show that pro-inflammatory M1-like macrophages, but not naive or M2 macrophages, accumulate in metabolic tissues, including visceral white adipose tissue and liver, during ageing and acute responses to inflammation. These M1-like macrophages express high levels of the NAD-consuming enzyme CD38 and have enhanced CD38-dependent NADase activity, thereby reducing tissue NAD levels. We also find that senescent cells progressively accumulate in visceral white adipose tissue and liver during ageing and that inflammatory cytokines secreted by senescent cells (the senescence-associated secretory phenotype, SASP) induce macrophages to proliferate and express CD38. These results uncover a new causal link among resident tissue macrophages, cellular senescence and tissue NAD decline during ageing and offer novel therapeutic opportunities to maintain NAD levels during ageing.
https://www.ncbi.nlm...les/PMC7908681/
3. CD38 hydrolyses NAD+ to NAM and ADP-ribose:
https://reactome.org...l/R-HSA-8938076
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I have a guess. Defective mitochondria are not only found in senolytic cells. They are also found in ordinary cages.
Total SASP = SASP (senescent cells) + SASP (mitochonria not in senescent cells).
This may explain why the NAD + level begins to fall until the age of 40, when the number of senescent cells is still small.
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We need to break the axis: [defective mitochondria] - [SASP] - [increase in M1 macrophages] - [increase: CD 38 receptors on macrophages M1] - [decrease: NAD +]
To reduce the number of defective mitochondria, you can use the property: mitochondria are checked for quality after the division procedure. Defective mitochondria are removed. This procedure must be carried out 15-20 times until the defective mitochondria are almost completely removed.
For these purposes, you can use the protocol that Turnbuckle developed. This protocol is on our forum.
Edited by Kentavr, 12 August 2021 - 04:36 PM.